Their chaperone, a Border Patrol agent, called out from behind the wheel: "Good luck, bro! I'm sure you can, but good luck."

As debate swirled, Antonio described ways that the 30-foot-high wall could be defeated, which prompted the lone woman to finally ask in faux suspicion: "Are you from Mexico?"

Most of the nearly dozen participants in the El Centro Sector Border Patrol citizens' academy were, in fact, of Mexican descent. And the mood was light as they learned about an agency they one day hope to join.

President Trump has called for hiring 5,000 more Border Patrol agents as part of his war on illegal immigration. If that happens, the academy in this Imperial Valley, California, town last month offered a snapshot of many of those likely to apply: Latinos.

When the Border Patrol was established in 1924, Latinos were a tiny minority. By 1989, they made up almost 36 percent of the agency. Now Latinos make up a little more than 50 percent of the Border Patrol, according to 2016 data.

This year, 10 out of the 11 people taking part in the Border Patrol citizens' academy are Latino.

Being a Border Patrol agent and Latino has always been potentially fraught, with immigrants from Latin America, especially Mexico, long the focus of often vitriolic debates over illegal immigration. But with Trump reserving his most heated rhetoric for immigrants coming from Mexico and Central America — and promising massive walls to keep them out — it has rarely seemed as delicate a tightrope.

Jonathan Pacheco, a nearly 10-year veteran, said being a Border Patrol agent and Latino has always guaranteed some complicated moments.

"I got it initially when I first came in, the 'Don't you feel bad, you're catching your own people. They're just coming over here to work,'" he said. "A lot of the people, and I try to use good verbiage because I know that anytime anyone hears anything about, 'Well some of the people coming across have done illegal things,' they always go back to what Trump said during his campaign."

Pacheco, whose parents came from Mexico on legal visas before eventually becoming U.S. citizens, added: "I don't want to say everything he said is true or not true. But at a Border Patrol level ... a lot of these people who come here are usually apprehended for the second or third time. A lot of these guys already have previous records."

"This is something I know burns inside a lot of the Hispanic candidates — is what do I say, what does this mean, to arrest somebody from my own, maybe my parents' hometown," Zamora said. "It's real simple: It's the law. It is right and wrong. It is not against any one race or any one ethnic group or any one particular group of people."

With so many of the immigrants crossing the border illegally from Mexico and Latin America — and many border towns being majority Latino — recruiting people who are more likely to speak Spanish has always made sense, experts said.

"There have been Latino agents, namely Mexican-Americans, since the very beginning of Border Patrol," said Kelly Lytle Hernandez, a UCLA professor and author of Migra! A History of the U.S. Border Patrol. "Of course, through the '70s really they were a minority, but they were actively recruited as early as the 1920s for their language abilities in particular."

The majority of trainees in the El Centro Border Patrol academy this year grew up near the border. Unlike many young Latinos in urban and often more liberal areas, they refer to those in the country illegally simply as "illegals."

Some trainees have family members who work for the Border Patrol. Manuel Trujillo has a stepfather in the Border Patrol. Eighteen-year-old Eduardo Segura's parents pushed him to follow in the footsteps of his older sister, who is an agent. One of Isaac Antonio's aunts is in the Border Patrol.

Antonio's maternal grandparents are from Mexico. On his father's side, his grandfather is from the Philippines and his grandmother from Mexico.

At times, Antonio has found himself arguing with friends over his desire to join the Border Patrol. Those debates have become more common and intense since Trump's election.

Antonio, who hails from El Centro, said friends have told him they can't believe he wants to arrest his "own people." He said that he responds by saying: "I'm protecting my people. My people are here." But he said it can be complicated.

Last year, he spotted two immigrants jumping over a border fence. When a Border Patrol agent headed in their direction, Antonio said one of his friends shouted a warning in Spanish. In that moment, Antonio said he remembered thinking: "Run."

"I know sometimes most of them just want to come over here for a better future," he said.

But Antonio said he dreams of being a Border Patrol agent, and there's no doubt that he would do his job.

"You do arrest people who are like — 'What if that was my uncle?' If it was my uncle," he said before pausing, "I would arrest him. But I wouldn't be able to, like, physically do it. I would have another agent do it."

Jose Avalos, one of the trainees, would not have been born in the U.S. had his mother, Fanny Posada, not crossed the border illegally in 1987. She left Mexico to provide for her young family. Posada left Avalos' older brother with her mother and hopped a bus from Mexico City to Tijuana.

After that, she trekked through the desert for hours with 40 other people, led by a guide who would get paid by an aunt if he got Posada into California. When he saw car lights approaching, the guide panicked and ran down a hill, leaving Posada and others to fend for themselves.

Posada said she has vivid recollections of a helicopter flying overhead and a Border Patrol agent with a gun out of his holster in the distance.

Posada hid in a bush until everything went quiet. Eventually, she made it to a store in California, and the owner called the number written on Posada's arm for her aunt to come get her.

She obtained a work permit her first year in the U.S., after laboring in a Lodi vineyard.

Fourteen years later, in 2001, Posada applied to join the Border Patrol. She had been encouraged by her next-door neighbor, who was an agent.

Her neighbor pushed her to get her GED and her residency. When Posada didn't have the money to get her citizenship, the agent wrote her a check.

Posada said the fact that she had been born in Mexico influenced a question she was asked during her interview with the Border Patrol. The agents asked how they could be sure that she wouldn't let immigrants go free.

"You're paying me and I have to do my job," Posada said she responded. "But I'm not going to be mean to them, and I'm going to try and tell them how they can try legally. That I will try to share with them — because I know they're nice people, they're just looking for employment. Now if I found someone with drugs, I probably won't be that nice."

In the end, Posada did not join the Border Patrol because she had no one to watch her children while she attended the academy. Instead, she began working for the city of Brawley, where she has been for 17 years.

In September, Avalos, 28, applied to become an agent. He said he wanted a job that could provide a good life for his wife and himself. Like his mother, he said that he was inspired by their neighbor, the Border Patrol agent.

He has taken the polygraph test and hopes that Trump's pledge to hire more agents means he'll be able to start his career soon.

"People might say, 'Oh, you don't care about your culture,'" Avalos said. "I love everything about my culture, but I was born here and I consider myself American."

On a Saturday last month, trainees stood on a drag road in Calexico under a gloomy sky. The traffic in the much larger Mexican city of Mexicali was visible through an 18-foot bollard-style fence.

They formed a semicircle around Agent Juan Gonzalez as he pointed out their footprint patterns in the dirt, identifying them as honeycomb or waffle iron. Those footprints can help agents locate people who jumped the fence by calling in the pattern over the radio to the agent on the next drag road.

Michael Araujo, one of the trainees, has uncles who crossed illegally and later fixed their papers. The father of a close friend was deported and lives on the Mexican side of the border, where the family visits him every other weekend.

"I know how much that's a struggle, and I feel bad for those situations where the family is separated," 19-year-old Araujo said. "For most people, when you sign up for this you realize you're most likely not allowing someone to maybe visit their family, maybe they already have family here. It's a major conflict internally, but it has to be done."

Like many other trainees, Araujo said a major reason for wanting to join the Border Patrol is a simple one: It's a job in a county with the second-highest unemployment rate statewide at 17 percent. The Border Patrol is one of the top employers in Imperial County.

On an agent's salary, "here in Imperial Valley, you'll be upper-middle class," Gonzalez told the group.

"Everyone's kind of interested if you're from around here," Araujo said. "They know it's one of the few places you can get a good job."

Excerpted from an article that originally appeared in the Los Angeles Times. Reprinted with permission.